The 114,500-ton Costa Concordia luxury liner has been rotting on an Italian reef since last January, after a collision that killed 32 of the 4,229 passengers and crew on board and has left the ship stranded for nearly 24 months. This morning, a crew of more than 500 engineers is attempting to finally right the Costa Concordia in the single-largest maritime salvage operation of all time. Here's how they're getting it done.

The Costa Concordia has spent the last year and a half resting in about 65 feet of water, atop a pair of underwater granite peaks a few yards offshore, tilting 70 degrees to starboard. While roughly half of the ship remained above water, the entire wreck is dangerously close to the edge of the reef that sank it, which sits above a 230-foot deep trough that could submerge it entirely.

Advertisement

Today, crews are attempting the first of five phases needed to right the vessel so that it can be towed to a scrap yard and dismantled. A series of cement sacks and a steel platform have already been installed on the reef to stabilize the wreck, and a floating boom has been deployed to capture any remaining fuel, oil, or other hazardous liquids that might spill out as the ship is righted. Nearly 350 cubic meters of diesel, fuel, and other lubricants have already been offloaded to prevent an ecological catastrophe should something go wrong.

"The size of the ship and its location make this the most challenging operation I've ever been involved in," Nick Sloane, chief salvage operator, told the Daily Mail. In fact, this is the largest recovery op ever attempted on a passenger ship.

The actual raising involves a complex series of ropes, pulleys, and hydraulic jacks. In addition, a series of 11 mammoth steel boxes, dubbed sponsons, some of which are 11-stories tall, have been welded to the port side (as you can see above). These boxes are being flooded with seawater to help entice the ship onto a more even keel. Crews hope this will occur without tearing the ship in two, which is a very real possibility. Engineers estimate that it will result in only slightly buckling the superstructure, however, nobody knows how firmly the ship is wedged into its perch or how much force will really be required to free it.

“Once you start lifting her off the reef you have already gone beyond the point of no return,” Sloane, told the Telegraph last Friday. If successful, the Costa Concordia will roll off its granite peaks—its weakened bow braced by a pair of steel "blister tanks"—and onto an artificial reef constructed of six steel-cement platforms before being towed away and scrapped next spring.

In all, the project is expected to use more than 30,000 tons of steel in the construction of these platforms as well as the rest of the equipment that will be employed during today's 12 hour operation. It will be raised slowly in order to minimize structural shock and, with any luck, right the ship in one piece, as well as allow ROV's to explore previously inaccessible areas for the two remaining missing victims.

This 14 month recovery project has already passed the €600m ($800m) mark with a final price tag estimated to be as much as $1.1 billion. The project is being paid for through Costa Crociere's insurance.

The parkbuckling project has been underway for roughly three hours now as an overnight storm delayed the operation slightly. Crews are currently performing the most delicate steps of the salvage, employing hydraulic jacks and pulleys to slowly pry the giant ship from its perch. [Daily Mail - Telegraph - Sky News - Chicago Tribune]